WAEC Agricultural Science Past Questions and Answers (Practice)

These are WAEC-style Agricultural Science questions (2020–2024 trend). They cover soil science, crop production, animal husbandry, tools, economics, pests, irrigation and food storage. Numbering starts from WAEC Q1 to make it easy to follow.

A. Soil Science, Soil Fertility and Erosion (WAEC)

WAEC Question 1. State four main components of soil.

Answer: (i) Mineral matter (sand, silt, clay); (ii) Organic matter (humus); (iii) Soil water; (iv) Soil air; (v) Living organisms (earthworms, bacteria, fungi, insects). (Any four)

WAEC Question 2. List three physical properties of soil that affect crop production.

Answer: (i) Soil texture (relative amounts of sand, silt and clay); (ii) Soil structure (arrangement of soil particles); (iii) Soil porosity; (iv) Soil colour; (v) Soil temperature. (Any three)

WAEC Question 3. Mention three characteristics of sandy soil and two advantages of using it for crop production.

Answer:
Characteristics: (i) Large particles and large pore spaces; (ii) Very well-drained; (iii) Low water-holding capacity; (iv) Low in nutrients. (Any three)
Advantages: (i) Easy to till; (ii) Warms up quickly for early planting; (iii) Suitable for crops that do not like waterlogging, e.g. groundnut. (Any two)

WAEC Question 4. State three ways in which organic matter improves soil fertility.

Answer: Organic matter: (i) Adds plant nutrients when it decomposes; (ii) Improves soil structure and aggregation; (iii) Increases water-holding capacity; (iv) Increases cation exchange capacity (CEC); (v) Provides food for soil organisms. (Any three)

WAEC Question 5. (a) Define soil erosion. (b) State three human activities that cause soil erosion in Nigeria.

Answer:
(a) Soil erosion is the removal and carrying away of the topsoil by agents such as water, wind and ice.
(b) Human activities: (i) Bush burning; (ii) Overgrazing; (iii) Deforestation; (iv) Continuous cropping without cover; (v) Wrong tillage on steep slopes. (Any three)

WAEC Question 6. Mention four soil conservation measures suitable for sloping land.

Answer: (i) Contour ridging or contour ploughing; (ii) Terracing; (iii) Strip cropping; (iv) Planting cover crops; (v) Mulching; (vi) Establishing windbreaks or shelterbelts. (Any four)

WAEC Question 7. List three chemical methods of maintaining soil fertility.

Answer: (i) Application of inorganic fertilizers (e.g. NPK, urea); (ii) Liming of acidic soils; (iii) Use of rock phosphate; (iv) Application of micronutrient fertilizers. (Any three)

B. Crop Production and Farming Systems (WAEC)

WAEC Question 8. Define crop rotation and state two reasons why it is practised.

Answer: Crop rotation is the planned growing of different crops on the same piece of land in a definite sequence over a number of years. Reasons: (i) To maintain soil fertility; (ii) To reduce build-up of pests and diseases; (iii) To control weeds; (iv) To make better use of plant nutrients. (Any two)

WAEC Question 9. Differentiate between mixed cropping and mixed farming.

Answer: Mixed cropping is the growing of two or more crops on the same piece of land at the same time, while mixed farming is the combination of crop production and livestock rearing on the same farm.

WAEC Question 10. List four field operations carried out on a maize farm after planting.

Answer: (i) Thinning; (ii) Gap filling; (iii) Weeding; (iv) Fertilizer application or manuring; (v) Pest and disease control; (vi) Harvesting. (Any four)

WAEC Question 11. State three factors to consider when choosing a site for vegetable production.

Answer: (i) Nearness to water source; (ii) Fertility and depth of soil; (iii) Good drainage; (iv) Nearness to market; (v) Protection from animals and strong winds. (Any three)

WAEC Question 12. (a) What is seed dormancy? (b) State three ways of breaking seed dormancy.

Answer:
(a) Seed dormancy is a condition in which a viable seed fails to germinate even when conditions are favourable.
(b) (i) Scarification (scratching or nicking the seed coat); (ii) Soaking seeds in water; (iii) Treating seeds with chemicals (e.g. acids or hormones); (iv) Exposure to low temperature (stratification). (Any three)

WAEC Question 13. Give four examples of vegetative (asexual) propagation methods used in crop production.

Answer: (i) Use of stem cuttings (e.g. cassava); (ii) Budding; (iii) Grafting; (iv) Layering; (v) Use of suckers (e.g. banana, plantain); (vi) Use of tubers or tuber pieces (e.g. yam, Irish potato). (Any four)

WAEC Question 14. Mention three advantages and two disadvantages of mono-cropping.

Answer:
Advantages: (i) Easy use of machines; (ii) Simple management and supervision; (iii) Easier pest and weed control because one crop is involved. (Any three)
Disadvantages: (i) Greater risk of total crop failure; (ii) Faster spread of pests and diseases; (iii) May reduce soil fertility quickly. (Any two)

C. Animal Husbandry – Cattle, Poultry and Fish (WAEC)

WAEC Question 15. State three advantages of artificial insemination (AI) in cattle production.

Answer: (i) One superior bull can serve many cows; (ii) Reduces the risk of spreading venereal diseases through natural mating; (iii) Reduces the cost of keeping many bulls; (iv) Semen can be stored and transported easily. (Any three)

WAEC Question 16. List four signs of heat (oestrus) in a cow.

Answer: (i) Restlessness; (ii) Mounting other animals or allowing others to mount it; (iii) Swollen and reddish vulva; (iv) Mucous discharge from the vulva; (v) Drop in milk yield. (Any four)

WAEC Question 17. Mention four management practices carried out on day-old chicks in a brooder house.

Answer: (i) Provision of adequate heat; (ii) Provision of clean water and balanced chick mash; (iii) Vaccination according to schedule; (iv) Beak trimming where necessary; (v) Regular cleaning and disinfection of brooder; (vi) Stocking at recommended density. (Any four)

WAEC Question 18. State three differences between layers and broilers.

Answer: (i) Layers are reared mainly for egg production, while broilers are reared mainly for meat; (ii) Layers take longer to reach maturity, broilers grow faster; (iii) Feed for layers is balanced for egg laying, feed for broilers is balanced for rapid growth; (iv) Layers usually have lighter body size than broilers. (Any three)

WAEC Question 19. List three signs of good health in farm animals.

Answer: (i) Bright, clear eyes; (ii) Smooth, shiny coat or feathers; (iii) Normal appetite and rumination; (iv) Alertness and active movement; (v) Normal body temperature and breathing. (Any three)

WAEC Question 20. Mention three management practices in a fish pond to ensure good fish growth.

Answer: (i) Regular feeding with balanced fish feed; (ii) Maintaining correct water level and quality; (iii) Removal of predators and weeds; (iv) Regular checking of dissolved oxygen; (v) Grading and thinning overcrowded fish. (Any three)

D. Farm Tools and Equipment (WAEC)

WAEC Question 21. State three differences between simple farm tools and farm implements.

Answer: (i) Simple farm tools are hand-operated, while implements are animal- or tractor-drawn; (ii) Simple tools are light and small, implements are larger and heavier; (iii) Simple tools are cheap and easy to repair, implements are more expensive and need skilled maintenance.

WAEC Question 22. List five examples of simple farm tools and state one use of each.

Answer: (i) Cutlass – clearing bushes and cutting weeds; (ii) Hoe – tilling the soil and making ridges; (iii) Rake – gathering trash and levelling the soil; (iv) Spade – digging and lifting soil; (v) Wheelbarrow – carrying materials such as manure, seedlings and tools.

WAEC Question 23. Mention four maintenance practices for farm tools and implements.

Answer: (i) Washing and cleaning after use; (ii) Drying and storing in a dry place; (iii) Sharpening cutting edges regularly; (iv) Oiling or greasing metal parts; (v) Repairing or replacing broken handles. (Any four)

E. Agricultural Economics and Marketing (WAEC)

WAEC Question 24. Define agricultural marketing.

Answer: Agricultural marketing is the process of moving farm products from the farm to the final consumers in the right form, place and time, and at a price that gives profit to the farmer.

WAEC Question 25. State four functions of middlemen in agricultural marketing.

Answer: (i) Assembling products from many farmers; (ii) Transporting goods to markets; (iii) Storing products until they are needed; (iv) Providing market information; (v) Bearing some risks such as spoilage and price changes. (Any four)

WAEC Question 26. List four problems faced by small-scale (peasant) farmers in Nigeria.

Answer: (i) Lack of credit facilities; (ii) Use of crude tools and low technology; (iii) Small farm size; (iv) Poor storage and processing facilities; (v) Poor roads and markets. (Any four)

WAEC Question 27. State three reasons why keeping farm records is important to a farmer.

Answer: (i) To know profit or loss; (ii) To help in planning and decision making; (iii) To obtain loans from banks; (iv) To compare performance over the years. (Any three)

F. Pest, Disease, Irrigation, Preservation and Storage (WAEC)

WAEC Question 28. Define a pest and give two examples of crop pests.

Answer: A pest is any organism that causes damage to crops or farm animals and reduces yield or quality. Examples: Grasshopper; Stem borer; Armyworm; Weevil; Termite. (Any two)

WAEC Question 29. State four methods of controlling crop pests, giving one example each.

Answer: (i) Cultural control – crop rotation, early planting, proper weeding; (ii) Biological control – using predators or parasites, e.g. ladybird beetles to control aphids; (iii) Chemical control – using insecticides, fungicides, herbicides; (iv) Mechanical control – hand picking, traps, fencing.

WAEC Question 30. State three ways of preventing the spread of diseases in a poultry farm.

Answer: (i) Regular vaccination of birds; (ii) Quarantine of new or sick birds; (iii) Proper cleaning and disinfection of houses and equipment; (iv) Provision of clean water and balanced feed; (v) Control of rodents and wild birds. (Any three)

WAEC Question 31. (a) What is irrigation? (b) Mention three types of irrigation.

Answer:
(a) Irrigation is the artificial application of water to the soil to supply the moisture required by crops.
(b) Types: (i) Furrow irrigation; (ii) Sprinkler irrigation; (iii) Drip (trickle) irrigation; (iv) Basin or flood irrigation. (Any three)

WAEC Question 32. List three problems of irrigation farming in Nigeria.

Answer: (i) High cost of construction and maintenance; (ii) Waterlogging and salinisation of soils; (iii) Spread of water-borne diseases; (iv) Poor management and siltation of canals. (Any three)

WAEC Question 33. State four traditional methods of preserving harvested food crops in Nigeria.

Answer: (i) Sun-drying; (ii) Smoking; (iii) Salting; (iv) Fermentation; (v) Use of ash; (vi) Storing grains in mud silos or cribs. (Any four)

WAEC Question 34. List three modern methods of food storage used in large farms and agro-industries.

Answer: (i) Cold storage / refrigeration; (ii) Canning; (iii) Freezing; (iv) Use of silos and metal bins for grains; (v) Use of cold rooms. (Any three)

WAEC Question 35. State three reasons why proper storage of farm produce is important to farmers.

Answer: (i) To reduce losses from pests and spoilage; (ii) To sell when prices are better; (iii) To ensure steady supply of food throughout the year; (iv) To maintain quality and nutritional value of produce. (Any three)

NECO Agricultural Science Past Questions and Answers (Practice)

These questions follow NECO style and common patterns from 2020–2024. Numbering starts again from NECO Question 1. Use them to test your readiness for NECO Agricultural Science.

NECO Question 1. State three differences between subsistence farming and commercial farming.

Answer:
Subsistence farming: (i) Small farm size; (ii) Mainly family labour; (iii) Low level of technology and low output used mainly for family consumption.
Commercial farming: (i) Large farm size; (ii) Uses hired/skilled labour; (iii) High level of technology and high output mainly for sale.

NECO Question 2. List four importance of agriculture to the Nigerian economy.

Answer: (i) Provides food for the population; (ii) Provides raw materials for industries; (iii) Provides employment; (iv) Earns foreign exchange; (v) Contributes to national income (GDP); (vi) Provides market for industrial goods. (Any four)

NECO Question 3. Define tillage and mention its two main types.

Answer: Tillage is the mechanical manipulation of the soil to prepare a good seedbed for plant growth. Types: (i) Primary tillage; (ii) Secondary tillage.

NECO Question 4. State three reasons for land clearing before crop production.

Answer: (i) To remove trees, shrubs and weeds; (ii) To make farm operations easier; (iii) To reduce hiding places for pests and dangerous animals; (iv) To allow for farm layout and mechanisation. (Any three)

NECO Question 5. Name three classes of farm animals based on their digestive system and give one example of each class.

Answer: (i) Ruminants – Cattle, sheep, goats; (ii) Non-ruminants (monogastrics) – Pigs, poultry; (iii) Pseudo-ruminants – Horse, rabbit.

NECO Question 6. List four pasture improvement practices.

Answer: (i) Reseeding with improved pasture species; (ii) Fertilizer application; (iii) Controlled or rotational grazing; (iv) Weed control; (v) Irrigation during dry season. (Any four)

NECO Question 7. State three characteristics of a good poultry house.

Answer: (i) Well ventilated; (ii) Dry and well-drained floor; (iii) Adequate space per bird; (iv) Protection from predators and thieves; (v) Easy to clean and disinfect. (Any three)

NECO Question 8. List four common nutritional deficiency diseases in farm animals.

Answer: (i) Rickets (vitamin D deficiency); (ii) Night blindness (vitamin A deficiency); (iii) Beri-beri (vitamin B₁ deficiency); (iv) Anaemia (iron deficiency); (v) Goitre (iodine deficiency). (Any four)

NECO Question 9. Explain zero grazing as a system of animal production.

Answer: Zero grazing is a system where animals are kept in confinement and fodder is cut and taken to them instead of allowing them to roam and graze freely.

NECO Question 10. List three factors that can affect the supply of agricultural products in the market.

Answer: (i) Price of the product; (ii) Cost of production; (iii) Weather and climatic conditions; (iv) Government policies and taxes; (v) Availability of storage and processing facilities. (Any three)

NECO Question 11. State three advantages of farm mechanisation in Nigeria.

Answer: (i) Increases the area of land that can be cultivated; (ii) Saves time and reduces drudgery; (iii) Improves timeliness and efficiency of farm operations; (iv) Leads to higher productivity per farmer. (Any three)

NECO Question 12. Mention three disadvantages of using chemical herbicides to control weeds.

Answer: (i) They may pollute soil and water; (ii) They may kill useful plants and soil organisms; (iii) Weeds may develop resistance; (iv) They can be harmful to farmers if misused. (Any three)

NECO Question 13. List three methods of harvesting fish in a fish pond.

Answer: (i) Draining the pond; (ii) Using drag nets or cast nets; (iii) Using hooks and lines; (iv) Using traps. (Any three)

NECO Question 14. State three advantages of keeping accurate farm records.

Answer: (i) Help to know profit or loss; (ii) Help in planning and decision making; (iii) Needed to obtain loans or credit from banks; (iv) Help to compare farm performance from year to year. (Any three)

NECO Question 15. List three environmental factors that affect crop growth.

Answer: (i) Light; (ii) Temperature; (iii) Water / rainfall; (iv) Wind; (v) Soil nutrients. (Any three)

Exam Tips for WAEC & NECO Agricultural Science

1. How to Answer Agricultural Science Practical Questions

• Read the instruction carefully. Note key words like state, list, describe, explain, sketch or label. Your answer length depends on the command word.
• Use point form for “state” or “list”. Write each point on a new line. Avoid long stories.
• Identify specimens correctly. When given tools, seeds, feeds or organs, write the specimen letter (A, B, C), the correct name and the required class, use or description.
• Use correct agricultural terms. Say “disc plough” not “iron with many plates”; “culling” not “removal of useless animals”; “irrigation” not just “watering”.
• Answer exactly what they ask. If the question says “state two”, write only your best two points first. Examiners mark from the top.
• Draw neat, simple diagrams. When they say “sketch” or “draw”, use a sharp pencil, draw simple outlines and label straight lines with a ruler.
• Write legibly. If the examiner cannot read your answer, you may lose marks even when you are correct.

2. Important Diagrams to Know and Label

WAEC and NECO love diagrams. You should be able to draw and label the following clearly:

• Parts of a flower – sepal, petal, stamen (anther, filament), pistil (stigma, style, ovary, ovule).
• Structure of a maize grain – pericarp, endosperm, embryo, plumule, radicle.
• Parts of a dicot seed – seed coat, cotyledon, embryo, hilum, micropyle.
• Parts of the egg of a fowl – shell, shell membranes, albumen, chalazae, yolk, germinal disc, air space.
• Digestive system of a ruminant – mouth, oesophagus, rumen, reticulum, omasum, abomasum, small and large intestine.
• Digestive system of a poultry bird – beak, crop, proventriculus, gizzard, intestine, cloaca.
• Simple farm tools – cutlass, hoe, rake, spade, wheelbarrow, with one use each.
• Tractor and implements – side view of tractor showing engine, radiator, driver’s seat, rear wheel, PTO shaft; simple sketch of disc plough, harrow and ridger.
• General layout of a farmstead – farmhouse, store, animal houses, crop fields, access roads, water source, refuse dump.
• Types of irrigation – furrow, sprinkler, drip (simple labelled sketches).
• Fish pond cross-section – dyke, inlet, outlet, water surface, pond bottom.

3. Common Agricultural Science Mistakes to Avoid

• Confusing key definitions. Many students mix up mixed cropping and mixed farming, or pasture and forage. Learn short, clear definitions and examples.
• Writing stories instead of points. Examiners give marks for clear agricultural points, not for long English. Go straight to the point.
• Ignoring units. When writing stocking rate, seed rate or fertilizer rate, include correct units like kg/ha or birds/m² when you know them.
• Neglecting practical notebooks. Some students only read theory and ignore their practical notes and specimen lists. Practical questions carry many marks; revise them well.
• Poor time management. Spending too long on one difficult question can make you rush others. Start with questions you know well, then come back to difficult ones.
• Illegible handwriting and rough diagrams. If your work is rough or too tiny, the examiner may miss your points. Write neatly and label diagrams clearly.